Ibuprofen disposition in obese individuals

Arthritis & Rheumatology (Impact Factor: 7.76). 10/1985; 28(10):1117-21. DOI: 10.1002/art.1780281006
Source: PubMed


Eleven obese subjects (weight 114 +/- 11 kg, mean +/- SE) and 11 age-matched subjects with normal body weight (61 +/- 3 kg) were given 600 mg of ibuprofen orally after an overnight fast. Peak ibuprofen concentration was significantly decreased in obese subjects (P less than 0.02), although the time from administration to peak concentration was not different. Ibuprofen volume of distribution was increased in obese subjects, and this increased distribution correlated positively with body weight (r = 0.82; P less than 0.001). Volume of distribution corrected for body weight was decreased in obese subjects, and this decrease correlated negatively with body weight. Ibuprofen clearance was also increased in obese subjects; the increase correlated positively with body weight (r = 0.81; P less than 0.001). Since the independent variables, volume of distribution and clearance, were increased in parallel in the obese subjects, the dependent variable, elimination half-life, was unchanged. Using mean values of distribution calculated from the 2 groups, ibuprofen distribution into body weight in excess of ideal body weight was found to be approximately 0.44 times as extensive as the distribution into ideal body weight. Furthermore, ibuprofen clearance increased in parallel with the volume of distribution and total body weight. Clinically, these data indicate that in obese patients, the ibuprofen dose may be increased without changing the dose interval, in order to achieve necessary plasma concentrations.

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    • "Vc; Volume of Central Compartment; # Calculated by GastroPlusͿ 7.0 * Calculated by ADMET Predictor; a Ref (Oliary et al., 1992); b Ref (Perez de la Cruz Moreno et al., 2006); c Ref(Avdeef et al., 1998); d Ref (Domanska et al., 2009); e Ref (Abernethy and Greenblatt, 1985);f Ref (Geisslinger et al., 1995); g Ref (Cordero et al., 1997); h Ref (Beetge et al., 2000); i Ref (Kasim et al., 2004); j Ref (GlaxoSmithKline, 2009); k Ref (Planinsek et al., 2011); l Ref(Loftsson et al., 2008); m Ref (Huang et al., 1986); n Ref (Vertzoni et al., 2010); o Ref (Peeters et al., 2008);p Ref (Mannisto et al., 1982); q Ref (Baxter et al., 1986); r Ref (Keating and Croom, 2007); s Ref (Fei et al., 2013); t Ref (Ige et al., 2013); u Ref (Yun et al., 2006); v Ref (Hooper et al., 1991); w Ref (Prajapati et al., 2012); x Ref (Dressman and Reppas, 2000); "
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